Because air pressure on Mars is 1/150th (<1%) of Earth’s, fixed wing aerial Mars rovers would have to fly at over 250 MPH just to stay aloft in the rarefied Mars atmosphere. While possible to achieve that velocity, landing under control over rocky terrain is difficult at such speeds. For scientific reconnaissance, the ‘dwell’ time over any region of interest is limited by such airspeeds. So ground level on Mars requires a kind of wing and propulsion design that might be comparable to flying at 100,000 feet on Earth–which is currently beyond a fixed wing design. Light-weight, high flap-speed robots might hold some promise for optimized flight at low Martian air pressures.

Multimode (flying/crawling) insect is being developed by Robert Michelson and his design team from the Georgia Tech Research Institute (GTRI), University of Cambridge (England), and ETS Labs.